Detections

Explore public detection logic contributed by the community across SIEM and rule languages.

1,235 detections

This detection correlates suspicious device code authentication behaviour in Azure AD with a successful creation of a Windows Hello for Business (WHfB) credential within the same 24 hours.

Microsoft allows specific application and resource combinations (permitted by CA) access without a previously registered device. Even more, one of these combinations allows the registration of a device.

An access token issued for the Microsoft Authentication Broker application and the Intune Enrollment resource can be used to authenticate and initiate the device join process.

Therefore, an attacker can leverage the token to bypass CA, register device, and establish persistence. Once registered, attacker gets a Primary Refresh Token (PRT), valid for 90 days.

Attackers often push further to configure WHfB (Windows Hello For Business) on the registered device. WHfB issues TPM-backed, cryptographic credentials that Entra recognizes as a strong, phishing-resistant, passwordless authentication method.

Device registration unlocks persistence, but WHfB unlocks the ability to bypass stricter authentication-strength requirements.

Analysts: Check for IP mismatches, since in the Device Code authentication event we will see the victims IP, the WHfB registration event will contain the attackers IP.
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Will Shaw@SheffShaw94
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Detections.ai Community
11 months ago
692428
This detection identifies cases where a successful device registration event in Azure AD occurs shortly after a successful Resource Owner Password Credentials (ROPC) authentication to Microsoft Intune Enrollment via the Microsoft Authentication Broker.

Microsoft allows specific application and resource combinations access without a previously registered device.

An access token issued for the Microsoft Authentication Broker application and the Intune Enrollment resource can be used to authenticate and initiate the device join process.

An attacker can leverage the token to bypass CA, register device, and establish persistence. Once registered, attacker gets a Primary Refresh Token (PRT), valid for 90 days.

The following query joins ROPC successful sign-ins, to successful device registrations. Registrations that occur soon after a ROPC event (2 days in this instance) could be an indicator of abuse.
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Will Shaw@SheffShaw94
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Detections.ai Community
11 months ago
381286
Detects GitHub Actions activity matching indicators used by Shai-Hulud 2.0 for exfiltration and persistence
Effy Elden@ineffyble
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Detections.ai Community
11 months ago
40138
Detects a pattern indicative of an NTLM relay attack following an authentication coercion spray. The rule first identifies a single source IP generating a high volume of failed NTLM logon attempts across multiple critical servers in a short time. It then looks for a subsequent successful NTLM logon from that same source IP to a high-value target (like a Certificate Authority) using a machine account. This sequence is a strong indicator that an attacker coerced credentials and is now relaying them to escalate privileges.
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Mehulkumar Savajani@Msavajani
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Detections.ai Community
11 months ago
180245
Microsoft Entra ID Protection can provide a broad range of risk detections that can be used to identify suspicious activity in your organization.

This KQL detection rule identifies and prioritizes high-fidelity user risk events in Azure AD. It focuses on high-fidelity risk event types, filtering out known, noisy, or low-fidelity events to ensure alerts are accurate, actionable, and reliable.
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Andre Zeemering@Azeemering
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Detections.ai Community
11 months ago
502580
The purpose of this query is to identify accounts that have logged in from multiple different countries within a short time window (last hour or last day).
This is typically used for security monitoring to detect suspicious or anomalous authentication behavior.
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Sagar Patel@sagar
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Detections.ai Community
11 months ago
450366
Detects when a user account is added to a local privileged group (sudo or wheel) on a Linux endpoint using the 'usermod' utility. This action grants the user administrative privileges and could be indicative of privilege escalation.
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ᴅᴜᴛᴄʜʙᴏʏ 😎@dutchboy
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DROID
1 year ago
152262
Query sign-ins with MFA success immediately following multiple failed sign-ins from different regions. Potential session hijack or AiTM (Adversary-in-the-Middle).


Error Code 0
Successful authentication
Normal successful login (validate carefully only when paired with suspicious failures)

Error Code 50053
Account locked or malicious IP
HIGH - Brute force attempts

Error Code 50074
MFA challenge not passed
HIGH - User failed MFA

Error Code 500121
MFA prompt timeout
MEDIUM - Possible MFA fatigue indicator

Error Code 50133
Session revoked or SSO artifact invalid
HIGH - Session hijacking indicator

Error Code 50076
MFA required but not provided
MEDIUM - Possible MFA bypass attempt
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Anoozilla HunterX@AnoozillaHunterX
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Detections.ai Community
1 year ago
564679
* Compare distances and times of consecutive sign-ins for the same user.
* Flag events where travel speed exceeds physical limits as potential unauthorized access.

Example: Same user signing in from Chennai to Mumbai (India) in 30 minutes triggers an alert.
Distance - 5,560 km.
Required speed - 11,000 km/h
The event is flagged as impossible travel.
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Anoozilla HunterX@AnoozillaHunterX
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Detections.ai Community
1 year ago
152306
Detects the use of the AADInternals PowerShell module, a tool used by threat actors like MERCURY and DEV-1084 for credential theft and privilege escalation in Azure AD environments.
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Tim Peck@timpeck
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Detections.ai Community
1 year ago
3276
This query analyzes login events to identify users with more than five failed login attempts. It filters for login-related events, groups the data by username, endpoint name, failure reason, login type, and associated indicators, then counts the number of failed attempts. The results are sorted in descending order of failed attempts to highlight potentially suspicious activity.
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Sagar Patel@sagar
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Detections.ai Community
1 year ago
80180
Detects various sensitive configuration modifications in AWS that could indicate malicious activity, such as privilege escalation, defense evasion, or data exposure. This rule looks for a curated list of API calls related to changes in IAM, EC2 security groups, S3 bucket policies, and logging configurations.
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ᴅᴜᴛᴄʜʙᴏʏ 😎@dutchboy
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DROID
1 year ago
180222
Detects when a user account is added to a local privileged group (sudo or wheel) on a Linux endpoint using the 'usermod' utility. This action grants the user administrative privileges and could be indicative of privilege escalation.
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ᴅᴜᴛᴄʜʙᴏʏ 😎@dutchboy
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DROID
1 year ago
71221
Detect unauthorized access by identifying new country sign-ins for users through AADSignInEventsBeta analytics.
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Sagar Patel@sagar
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Detections.ai Community
1 year ago
320242
Detects when a user in OneLogin assumes the identity of another user account. This could indicate an attacker using compromised credentials to impersonate another user or an insider abusing privileges.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
0025
This query identifies user sign-ins leveraging legacy authentication protocols in Azure Active Directory (AAD). Legacy authentication methods, such as IMAP, POP3, Exchange ActiveSync, SMTP, and older Outlook protocols, do not support modern security features like multi-factor authentication (MFA). Their use increases the risk of account compromise, brute force attacks, and credential theft.

Monitoring for legacy authentication activity is a critical security control to detect potential unauthorized access or accounts bypassing modern security protections.
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Marvens Decayette@IronBranded
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Detections.ai Community
1 year ago
250293
This KQL query identifies vulnerable VPN clients installed on endpoints that have High or Critical severity CVEs. VPN software is a high-value target for attackers because vulnerabilities can be exploited to bypass network access controls, intercept traffic, or gain remote access to internal networks.
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Marvens Decayette@IronBranded
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Detections.ai Community
1 year ago
230285
Detects user sign-ins occurring outside of predefined normal business hours and from locations not explicitly whitelisted. This rule aims to identify potentially unauthorized access attempts or compromised accounts being used at unusual times or from unexpected geographies.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
10107
Detects when an instance identity has taken an action that isn't inside SSM.
This can indicate that a compromised EC2 instance is being used as a pivot point.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
1078
Detects a successful login to the Microsoft Intune Company Portal which could allow bypassing Conditional Access Policies and InTune device trust using a tool like TokenSmith. The rule specifically looks for 'UserLoggedIn' operations with 'Success' status for the Microsoft Intune Company Portal ApplicationId, while excluding a specific ObjectId often associated with mobile device enrollment to reduce false positives.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
6062
Detects when Microsoft Cloud App Security (MCAS) reports a risky sign-in attempt due to an impossible travel scenario. This indicates a potential compromise of user credentials where an attacker logs in from a geographically distant location in a short timeframe, making physical travel impossible.
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SigmaHQ Detections@sigmaHQ
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SigmaHQ
1 year ago
1058
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